Drawing device for drawing wires

ABSTRACT

Drawing device particularly for the drawing of wire ( 38 ), having at least one drawing body ( 1 ) such as a draw plate ( 1 ) or the like; and at least one clamping means ( 10 ) for securing the wire ( 38 ) to the respective drawing body ( 1 ).

[0001] The present invention relates to a drawing device for the drawing of wires.

[0002] A drawing device in the sense of the present invention is particularly a so-called wirepuller or wire drawing machine.

[0003] Known wire drawing machines have one or multiple dies, one or multiple draw plates and, if applicable, guide pulleys. A wire extends through a die which is secured in a die holder and is wound on a draw plate arranged behind said die such that the drive-generated motion of said draw plate induces the wire to be pulled through the die. The cross-sectional area of the die opening is smaller than the cross-sectional area where the wire material is fed to the die. As a consequence thereof, the wire in the region of the die is plastically deformed and its cross-sectional area decreased. When applicable, such types of wire drawing machines will comprise a plurality of dies in series connection such that the wire is deformed over the course of several stages, respectively the wire's cross-sectional area will be decreased by degrees. If required, the wire will be tempered at points between these stages, respectively between said dies. Guide pulleys may guide the wire and effect changes in its direction.

[0004] Before the actual continuous drawing of the wire can be realized, the wire first has to be pulled or threaded in such a way that it will extend through all the dies of the wire drawing machine to the driven draw plate arranged behind the last die. To this end, the wire first has to be pointed. For forming a point on the wire, a so-called rolling mill is often used; a device which is separate from the drawing machine and, if applicable, a movable apparatus. Said rolling mill produces a point at an end of the wire, said point then being pulled through a die of the rolling mill. The wire point—which is, for example, several hundred millimeters long—is pulled on the other side of the die by pliers and subsequently clamped by drawing tongs connected to a draw plate. A number of wire coils are formed on the driven draw plate. The plate as well as the die are subsequently inserted into the drawing machine and the wire re-pointed and guided through the next die. This procedure is repeated for as many times as the number of dies.

[0005] This wire pulling procedure is a relatively expensive one when employing these types of known devices. In addition, there are some safety factors involved due to the risk of the wire clamped between the drawing tongs slipping out during operation.

[0006] It is thus the task of the present invention to produce a structurally simplified and inexpensive drawing device having improved operational reliability.

[0007] This task is solved by a drawing device in accordance with claim 1.

[0008] The task is additionally solved by a clamping means in accordance with claim 17.

[0009] Preferred embodiments of the invention comprise the subject matter of the subclaims.

[0010] The drawing body is preferably configured in disk or cylindrical shape, rotatably mounted, and can be urged into rotational direction by a drive means.

[0011] The present invention particularly provides for a drawing device for the drawing of a wire which comprises a drawing body as well as a clamping means.

[0012] The drawing body is particularly formed as a draw plate and preferably comprises one or two flanges extending radially in circumferential direction, between which the wire can be spooled.

[0013] The clamping means serves for the securing of the wire to the drawing body.

[0014] The clamping means can be switched into at least one open unclamped position as well as at least one closed clamped position. The clamping means is configured and arranged on said drawing body such that a clamped wire is firmly fixed to the drawing body essentially stationary when said clamping means is in its closed position, said fixed position of the wire especially being fixed relative the circumferential direction and/or the radial direction and/or the axial direction of the drawing body.

[0015] The invention will be described in the following using the example of a draw plate, whereby it must be emphasized that a drawing body of a different configuration is also likewise preferred.

[0016] The draw plate is preferably of rigid configuration and made of metal or plastic or another material.

[0017] The clamping means preferably has an axially guided member which generates a clamping force upon the corresponding axial displacement.

[0018] The clamping means preferably comprises a component guided in a threading which produces the clamping force. Said component is particularly a screw or screw-like member which can be actuated by tools such as screwdrivers, wrenches or the like or by elements such as levers or control wheels or the like which are solidly affixed to said component.

[0019] Preferably, a counter-force to the clamping force for clamping a wire in the clamping means acts on the draw plate in such a way that a clamping jaw or the like braces against said plate.

[0020] The clamping means is preferably arranged at or on a flange of the draw plate. The flange preferably has an opening in which at least a part of the clamping means is arranged. Said opening preferably extends from the flange's inward facing side into the flange interior.

[0021] It is furthermore preferred that said opening extends into the flange in radial direction.

[0022] According to a particularly preferred embodiment of the present invention, the clamping means is arranged at the radially outer peripheral surface of the flange.

[0023] If applicable, the flange comprises buffer bevels arranged on its inward facing side for guiding the wire from the radially lower edge of the flange to the flange's lateral surface.

[0024] Preferably, the clamping means is entirely or at least partly non-releasably connected to the flange of the draw plate.

[0025] The flange of the draw plate is preferably disposed with an axially internal recess which, if so required, may have a varying depth.

[0026] Said recess extends into the flange preferably in the axial direction of the draw plate and with increasing depth from the flange's inward facing side. The axial depth preferably increases toward the clamping means.

[0027] Said axial recess is preferably configured such that the flank bordering said recess in axial direction extends at a relatively small angle to the flange plane; said angle being preferably less than 45°, particularly preferable less than 30°, particularly preferable less than 20°, particularly preferable less than 15°, preferably less than 10°, particularly preferable being less than 5°. Especially preferred is the guiding of the wire to the clamping means along this flank extending at an angle to the flange plane.

[0028] In the sense of the present invention, the “flange inward facing side in axial direction” refers to that side of the flange which faces the area where the wire is spooled.

[0029] Particularly in the case of having two flanges, the “flange inward facing side” means the intermediate region between said flanges.

[0030] Preferably, the area of clamped wire is supported on the draw plate and particularly in the axial or radial direction.

[0031] The clamping means is preferably disposed with a first as well as a second clamping member, a configuration as clamping jaws is particularly preferred.

[0032] One or both of said clamping members is/are preferably guided in a guiding means; particularly preferred is in the radial and/or axial direction relative to the draw plate.

[0033] Preferably, the first and/or second clamping member is configured to be of beaked shape and arranged such that the wire to be clamped is received in its opening.

[0034] According to a preferred embodiment of the invention, the clamping force of the clamping means is adjustable.

[0035] This is realized, for example, by the clamping means having a screw which when turned increasingly stresses the wire to be clamped. The clamping force is particularly variable independent of the diameter of the wire to be clamped.

[0036] According to a preferred embodiment of the present invention, the drawing device comprises several dies in series connection. Each of said dies is associated with only one draw plate whereby, when applicable, the same draw plate is associated with a plurality of dies. It is furthermore preferred that a draw plate is disposed seriate after each die so that one draw plate is always positioned between two dies in adjacent series connection.

[0037] According to the present invention, each draw plate, or at least a part thereof, is either configured as or comprises a clamping means.

[0038] A drawing device according to the present invention is preferably utilized as follows:

[0039] A point is formed on the end of a wire to be drawn into the drawing device by a corresponding device for forming points such that its outer contour closes in upon its axis, meaning in particular that its diameter is decreased. This pointed segment of the wire preferably extends over a length of several hundred millimeters. The outer contour of the wire, meaning in particular the diameter which is produced during the pointing process, is arranged such that the wire will extend at least through the next die of the drawing device, whereby the end extended through can then be pulled farther along by means of manually-activated tongs or pliers, if necessary. It is further preferred that the pointed end is formed in such a way that the outer counter of said wire end will adapt to a plurality of consecutive dies or to all of said dies of the drawing device.

[0040] After the pointed end of the wire has been extended through the next die, it is pulled toward the next following draw plate and secured at this point in the clamping means. The clamping means drive is then subsequently actuated so that the wire is drawn subject to plastic deformation. The length of the wire drawn in such a way, respectively the number of windings which are spooled onto the draw plate is of such a configuration that the drawn length is sufficient to move the end of the wire in the drawing direction through the next die and to the next draw plate (if applicable) so that the wire can then be re-clamped at this new position. However, before the wire is actually moved through the next die to the adjacent draw plate and clamped at same, the end of the wire is re-pointed in essentially the previously described method such that its outer contour will adapt to the inner contour of the die across a certain length, for example that of several hundred millimeters.

[0041] However, as described above, the wire can alternatively also be pointed during the first pointing procedure such that the outer contour of a certain segment of said wire end is already adapted to the inner contour of the next following die. In this case, a renewed pointing procedure may be omitted, as applicable.

[0042] If necessary, additional dies can be considered for the first pointing procedure or pointing procedures could be undertaken in graduated stages such that, for instance, the end of the wire is re-pointed at every second die.

[0043] Many configuration possibilities hereto arise, although the mechanical properties of the wire itself also definitely need to be taken into account. In particular, this means that in those cases where the outer contour of the wire is too small subsequent the first pointing procedure, respectively its diameter is configured too small, the wire might break during the drawing process should the mechanical properties not be appropriate.

[0044] The present task is additionally solved by a clamping means in accordance with claim 17.

[0045] Preferred embodiments and examples of the present invention as given are not to be considered as restrictions to the invention.

[0046] In the following, the invention will be described in greater detail with reference to the drawings, which are not to be considered as restricting of the present invention, and which therein show:

[0047]FIG. 1 an exemplary embodiment of the invention in a schematic, partial sectional view;

[0048]FIG. 2 a view along the 2-2 line of FIG. 1; and

[0049]FIG. 3 a cutaway view along the 3-3 line of FIG. 1.

[0050]FIG. 1 shows a multi-part draw plate to which a clamping means 10 for clamping the end part of a wire is secured by means of an appropriate fastening means such as screw 12 or other such similar means.

[0051] Draw plate 1 further comprises one or more rotational symmetric bodies 14 coupled to a drive shaft 16 to be urged by a drive.

[0052]FIG. 2 shows a view along the 2-2 line from FIG. 1 in a partial sectional view.

[0053] Draw plate 1 is provided with a first disc-shaped flange 20 as well as a second disc-shaped flange 22. Area 24, having a smaller diameter than said flanges 20, 22 and in which the wire can be taken up, is situated axially between said flanges 20, 22.

[0054] At the flange inward facing side 26 which faces area 24 having smaller diameter, flange flank 28 is disposed with a recess 30 which extends toward clamping means 10 with increasing depth 32 at an angle 34 to the flange plane, as indicated schematically by dashed line 36, and in which the partly and schematically depicted wire 38 can be guided to said clamping means 10.

[0055] Clamping means 10 comprises neighboring clamping jaws 40, 42 between which wire 38 is clamped. To this end, the wire is first positioned between the substantially opened clamping jaws. Wire 38 is then fixed or clamped between said clamping jaws 40, 42 by means of screw 12. Clamping jaw 42 is disposed with axial guides 44. In addition or alternatively, the clamping jaws can be guided in radial direction relative draw plate 1.

[0056]FIG. 3 shows a cutaway view along the 3-3 line from FIG. 1.

[0057] Draw plate 1 is connected to drive shaft 16 by means of a screw 50 as well as centered on said drive shaft 16.

[0058] If applicable, said drive shaft is disposed with a coupler 52 which serves for the form-fit connection between drive shaft 16 and draw plate 1 in the rotational direction. Plate 22 is disposed with a disc-shaped section 54 extending in radial direction as well as a cylindrical flange 56 arranged radially within said section 54. Said cylindrical flange 56 extends essentially concentric relative drive shaft 16. Plate 20 is mounted radially inward on said cylindrical flange 56. An annular element 58 is arranged between plates 20, 22 in the radial outer region and braced against said plates 20, 22 in the axial as well as in the radial direction. A plurality of screws 16 tighten plates 20, 22 against annular element 58 upon which wire 38 can be spooled on its outer periphery. 

1. Drawing device, particularly for the drawing of wire (38), having: at least one drawing body (1) such as a draw plate (1) or the like; and at least one clamping means (10) for securing the wire (38) to the respective drawing body (1); characterized in that said clamping device (10) is configured such that the end of said wire (38) to be clamped is fixed essentially stationary at said drawing body (1) immediately following the closing of said clamping means (10), and particularly with respect to the circumferential and/or radial and/or axial direction of said drawing body (1).
 2. Drawing device according to claim 1, characterized in that said clamping means (10) comprises an axially guided member (12) which generates a clamping force.
 3. Drawing device according to one of the preceding claims, characterized in that said clamping means (10) comprises an element guided in a threading such as a screw (12) which generates a clamping force.
 4. Drawing device according to one of the preceding claims, characterized in that the counter-force to the clamping force with which the clamping means stresses the wire (38) acts on said drawing body (1).
 5. Drawing device according to one of the preceding claims, characterized in that said drawing body (1) has at least one flange (20; 22) extending essentially radially and circumferentially.
 6. Drawing device according to one of the preceding claims, characterized in that said clamping means (10) is arranged on a flange (20; 22) of said drawing body (1).
 7. Drawing device according to one of the preceding claims, characterized in that said flange (20; 22) of said drawing body (1) has at least one opening in which said clamping means (10) is at least partially arranged.
 8. Drawing device according to one of the preceding claims, characterized in that said clamping means (10) is at least partly non-releasably connected to a flange (20; 22) of said drawing body (1).
 9. Drawing device according to one of the preceding claims, characterized in that said flange (20; 22) of said drawing body (1) is disposed with an axially internal recess (30) in and/or through which the end segment of said wire (38) extends to said clamping means (10).
 10. Drawing device according to claim 9, characterized in that said recess (30) extends at varying depth into said flange (20; 22), and in particular such that said depth (32) increases toward said clamping means (10).
 11. Drawing device according to one of the preceding claims, characterized in that said clamping means (10) is configured such that said clamped wire (38) is supported against a flange (20; 22) of said drawing body (1), particularly in radial and/or in axial direction.
 12. Drawing device according to one of the preceding claims, characterized in that said clamping means (10) comprises at least one first clamping member such as clamping jaws (40) as well as at least one second clamping member such as clamping jaws (42) which come into contact with said clamped wire (38) during the clamping procedure.
 13. Drawing device according to claim 12, characterized in that at least one guiding means is provided which guides said first and/or said second clamping member essentially in radial and/or axial direction relative said drawing body (1).
 14. Drawing device according to one of claims 12 or 13, characterized in that said first and/or said second clamping member is configured of beaked shape.
 15. Drawing device according to one of the preceding claims, characterized in that the clamping force of said clamping means (10) is adjustable.
 16. Drawing device, particularly for the drawing of wires comprising a plurality of differently configured dies as well as a plurality of drawings bodies (1) each associated with one die, whereby said dies and said drawing bodies (1) are alternatively seriate, characterized in that said drawing bodies (1) each comprise a clamping means (10), whereby said drawing bodies (1) and/or said clamping means (10) are each configured in accordance with one of the preceding claims.
 17. Clamping means for a drawing device in accordance with one of the preceding claims. 